Trends in the prevalence of bloodstream infections in Spanish hospitals (2013-2023)

Bloodstream infections (BSI) represent a growing and significant issue due to their associated mortality, morbidity, and economic burden. This study aimed to assess the prevalence of BSI from 2013 to 2023, by type and onset, and to describe patients' characteristics and identified microorganisms.

Data from the point prevalence survey on infections and antimicrobial use in Spanish hospitals were analysed. Logistic regression was conducted to identify temporal trends and associations between different factors and hospital-acquired BSI (HA-BSI). Stepwise backward selection with bootstrap resampling was applied for refinement and internal validation.

From 2013 to 2023, a total of 578,780 patients were included and 12,968 patients had a BSI. The mean prevalence of BSI was 22.4‰ (HA-BSI: 11.1‰; community-acquired BSI (CA-BSI): 11.3‰). BSI prevalence rose from 18.0‰ in 2013 to 24.3‰ in 2023, corresponding to a significant 3.5% yearly increase in the odds of infection (OR 1.035, 95% CI 1.029-1.040). This upward trend was also observed for HA-BSI and CA-BSI, with significant increases in the odds of 1.1% (OR 1.011, 95% CI 1.004-1.019) and 5.7% (OR 1.057, 95% CI 1.049-1.065), respectively. The multivariate logistic regression model identified CVC use as the strongest factor associated with BSI with an overall aOR of 8.31 (95% CI 7.58-9.12). The most common microorganisms in HA-BSI were Gram-positive cocci (52.4%) while Enterobacterales were more prevalent in CA-BSI (47.5%). Antimicrobial resistance was significantly higher in HA-BSI for methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis, third-generation cephalosporin-resistant Escherichia coli, third-generation cephalosporin-resistant and carbapenem-resistant Klebsiella pneumoniae, and Pseudomonas aeruginosa.

The prevalence of BSI in hospitalised patients in Spain is high and has been increasing over the past decade for both HA-BSI and CA-BSI, underscoring the need for continued efforts to reduce BSI rates.